7.  The facts of the case, as submitted by the parties, may be summarised as follows.
8.  The applicant was born in 1977 in Uznach and lives in Rapperswil‑Jona, in the Canton of St Gallen.
9.  After originally training to be a hairdresser the applicant took up full‑time work as a shop assistant. In June 2002 she was forced to stop work owing to back trouble.
10.  On 24 October 2003 the applicant applied to the Disability Insurance Office of the Canton of St Gallen (“the Office”) for a disability benefit on account of her lower back and spinal pain.
11.  On 6 February 2004 she gave birth to twins. Her back pain had worsened further during the pregnancy.
12.  On 15 March 2005 the Office carried out a household assessment (Abklärung im Haushalt) at the applicant’s home, during which the applicant stated
(i)  that she suffered from constant back pain which often extended down to her left foot; that she had particular difficulty standing in the same place for any length of time and could not remain seated for more than ten minutes; that she could walk for half an hour, but not on a daily basis; and that the pain became worse when she was carrying the children;
(ii)  that she would have to work half-time for financial reasons since her husband’s net salary was just 3,700 Swiss francs (CHF) (approximately 3,602 euros (EUR)).
The report on the assessment concluded that the applicant’s capacity to perform household tasks was reduced by 44.6%.
In its report dated 2 May 2005 the Office found that the applicant should be classified
(i)  as a person in full-time paid employment (Vollerwerbstätige) up to the end of 2003;
(ii)  as a housewife (Hausfrau) between January and May 2004;
(iii)  as a person theoretically capable of working 50% (zu 50 % hypothetisch Erwerbstätige) as of June 2004.
13.  On 16 June 2005 Dr Ch.A.S. informed the Office that the applicant was unable to work more than half-time in a suitable occupation and that any increase in her working hours appeared to be ruled out.
14.  In a decision of 26 May 2006 the Office found that the applicant should be granted a benefit for the period from 1 June 2003 to 31 August 2004, but did not qualify for any benefit from 1 September 2004 onwards.
The Office arrived at this result by the following means.
With regard to the period from 20 June 2002 until the end of May 2004, it assessed the applicant’s degree of disability at 50% on the basis of a calculation of her income.
As to the subsequent period, the Office considered that the so‑called combined method should be applied, taking the view that even if she had not had a disability the applicant would have reduced her working hours following the birth of her children. It based that finding, in particular, on the applicant’s assertion that she felt able to work only half-time and wished to devote the remainder of her time to her household tasks and her children. Furthermore, on the basis of the household assessment referred to above, the Office estimated the applicant’s capacity to perform household tasks at 56% (that is to say, her degree of disability at 44%). When the formula set out below was applied, the degree of disability obtained on the basis of these various factors was only 22%, meaning that the applicant did not reach the minimum 40% degree of disability needed to trigger entitlement to a benefit:
50 % (paid employment): no loss of earnings0.5 x 0 % = 0 %
50 % (household tasks and childcare): 0.5 x 44 % = 22 %
Total[1] = 22 %
15.  The applicant lodged a complaint with the Office, which was dismissed on 14 July 2006. Following a fresh calculation the Office recognised the applicant as having a 27% disability, still below the minimum required in order to qualify for a benefit.
This figure was obtained by applying the combined method, using the following parameters:
50 % (paid employment): 0.5 x 10 % = 5 %
 50 % (household tasks and childcare): 0.5 x 44 % = 22 %
Total[2] = 27 %
In completing the first line of the formula, the Office took as a basis a hypothetical income (for full-time work) of CHF 48,585 (approximately EUR 47,308), calculated on the basis of the statistical data for the socio‑professional category to which the applicant, as an auxiliary worker (Hilfsarbeiterin), belonged. Working at a rate of 50%, the applicant would therefore have had a salary of CHF 24,293 if she had been able to continue working without any difficulty (Valideneinkommen). The Office estimated that, given her disability, the salary which the applicant would actually be able to earn in a suitable occupation would be CHF 21,863 (Invalideneinkommen). It therefore assessed the applicant’s degree of disability in respect of the “paid employment” component at 10%.
16.  On 14 September 2006 the applicant appealed against that decision.
Relying on Article 14 of the Convention, read in conjunction with Article 8, the applicant argued that
(i)  the method applied discriminated against the less well-off, as those persons who could afford not to do paid work were classified simply as housewives and could therefore be recognised as having a higher degree of disability and thus qualify more easily for a benefit;
(ii)  the way in which the degree of disability was calculated did not take sufficient account of the interplay (Wechselwirkungen) between the “household” and “paid employment” components;
(iii)  in reality, even if she only worked half-time, her degree of disability for the purposes of performing household tasks would increase well beyond 44% as a result.
17.  In support of her appeal the applicant submitted a medical report issued by Dr Ch.A.S. on 28 September 2006, in which the latter stated in substance that, in view of her state of health, the applicant could not engage in paid work on a half-time basis in the same way as someone without a disability, and that if she had to take up paid employment, her capacity to take care of the household and of her children would drop to around 10%.
18.  In a judgment of 30 November 2007 the Insurance Court of the Canton of St Gallen allowed the applicant’s appeal in part.
In a departure from the case-law of the Federal Court ..., it considered that the usual application of the combined method should be disregarded in favour of an “improved” version. In the court’s view, the basis for calculation should be the level of activity which the applicant might reasonably have resumed after the birth of her twins if she had not had health problems.
The Insurance Court found that the “household” component of the combined method, as that method was applied in the Federal Court’s case‑law, did not take sufficient account of the person’s disability.
According to the court, the Office had not taken into consideration the fact that the applicant could only take care of the household on a half-time basis, and had incorrectly calculated her incapacity for work on the basis of a twelve-hour working day.
Instead of taking as a basis the household assessment – which, in the Insurance Court’s view, should be applicable only to individuals who were engaged full-time in caring for the household – the Office should have examined the applicant’s actual capacity to perform household tasks, which had been established by a doctor.
The court also criticised the Office for not examining whether, if she had been in good health, the applicant would have been able to engage in paid work after the birth of her children. In particular, it noted that the report drawn up following the household assessment gave scant information as to the work entailed for the applicant in caring for her children (Betreuungsaufwand) and whether or not any possibilities existed for entrusting part of their care to other persons. As these factors had not been taken into consideration by the Office, the applicant’s degree of disability had been established on the basis of an incomplete set of facts. The court also considered it unlikely that the applicant would have worked only half‑time if she had been in good health, given her husband’s modest salary and what she could reasonably expect to earn as a hairdresser or auxiliary worker. The household assessment therefore appeared to be deficient in that respect also.
Consequently, the Insurance Court remitted the case to the Office for further investigation.
19.  The Office lodged an appeal against the Insurance Court judgment.
20.  In a judgment of 28 July 2008 (9C_49/2008) the Federal Court allowed the Office’s appeal, finding that the applicant was not eligible for a benefit.
In its reasoning the Federal Court began by describing the context in which it viewed the case, stating that
(i)  the aim of disability insurance was to provide cover for insured persons against the risk of becoming unable, for medical reasons, to carry on a paid occupation or perform household tasks which they had actually been able to carry out before becoming disabled and would still be able to perform if the event triggering the disability had not occurred;
(ii)  the aim was not to provide compensation in respect of activities which the insured persons would never have carried out even if they had remained in good health;
(iii)  this approach was designed to prevent situations in which, for instance, individuals who were well-off and had never previously worked could be recognised as having a disability if they developed health problems, even though they would probably never have worked had they remained in good health.
21.  Accordingly, the Federal Court considered that the combined method was not discriminatory. It found as follows:
“3.4 ... It is true that the combined method, as applied by the [Federal] Court in its settled case-law, may result in a loss of benefit where the insured person is more than likely – generally on account of the birth of a child – to cease paid employment, at least on a full-time basis. However, it is not the disability that [then] causes the loss of income; many people in good health also suffer a loss of income when they reduce their hours or stop working. The criticism of the combined method is directed at the fact that individuals (mostly women) suffer a drop in earnings when they reduce their working hours after having children. Nevertheless, this sociological reality is not the result of factors linked to the person’s health and should not therefore be covered by the disability insurance scheme. It does not give rise to any discrimination or other breach of the European Convention on Human Rights.”
Nevertheless, the Federal Court conceded that the interplay between the “household” and “paid employment” aspects was not taken sufficiently into account in the combined method. With regard to the applicant, however, it found
(i)  that the aggravation of her health problems as a result of her paid work should not be regarded as reducing her capacity to perform household tasks by more than 15%;
(ii)  that, accordingly, even taking the interplay in question into account, the applicant’s degree of disability did not reach the 40% minimum required in order to qualify for a benefit:
50 % (paid employment): 0.5 x 10 % = 5 %
 50 % (household tasks): 0.5 x (44 + 15 %) = 29.5 %
Total[3] = 34.5 %
The argument that her husband was unemployed, which was raised by the applicant for the first time before the Federal Court, was rejected on the grounds that it had not been relied upon in the court below and was not substantiated.
However, the Federal Court granted the applicant legal aid in view of her lack of means.
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